I'm trying to track down a source for an idea I saw in a documentary a while ago (sorry, no idea where!) It demonstrated how children learn differently at different ages, through showing them balancing an unevenly weighted bar (in other words, a bar that looks the same along its length, but is in fact heavier at one end).
Loosely, the programme suggested that: young children (toddlers?) can get such a bar to balance intuitively, through "trial-and-error"; slightly older children (5?) try to balance the bar half way, and so say "it won't balance"; older children again, understand that the bar is not evenly weighted and so once again realise that experimentation is needed to find the balancing point.
Am I completely imagining that I saw some research of this kind? Or does anybody know where I can find a link to such a piece of research?